The Skinny on Xylitol, Stevia, Aspartame and Other Sugar-free Stuff

Xylitol, an ingredient in many sugar-free gums and mints, leads to a rapid drop in blood sugar for dogs.

To most of you, it only makes sense to keep
that sugar-free German chocolate cake away from your German Shorthaired Pointer. Not
only is it made of chocolate (which everyone knows is verboten for
dogs), but it also might contain something far worse. But not everyone knows
of the evils
built into some breeds of sweeteners.

For example, last week I received this email
from a confused
dog owner: “I just read on the Internet that aspartame causes pets to go blind and get brain damage. Is this
true, or is it
only another Internet horror story?”

Well, yes. It’s another one of those online
rumors that
goes viral before anyone gets a chance to confirm its veracity.
Aspartame, while
probably not particularly good for anyone, has very few serious side
effects in dogs and cats that we
know of. Not at the doses offered in consumer products,
anyway.

But I
have a sneaking suspicion I know how the rumor got started. A few years ago, I received one of those mass
emails written
by a bereaved dog owner who claimed her dog suddenly went blind,
fell over and
died after eating sugar-free yogurt containing aspartame.

After searching the Internet thoroughly (she
claimed), the owner concluded that methanol
poisoning as a result of aspartame ingestion was what killed her
dog. The rumor
reportedly sent thousands of pet owners into spasms of artificial
sweetener-related anxiety.

But never fear: Aspartame
will typically not lead to sudden death. Not in dogs or cats.

Nonetheless, it is true that aspartame will be
metabolized
into methanol by the body. And because methanol toxicity can lead
to blindness
and brain damage in humans, thus (presumably) the rumor was born.

The thing is, methanol is metabolized differently in dogs and cats from in humans. A small amount of methanol may cause some gastrointestinal upset, but it's not likely that a mammal can eat enough
aspartame to cause serious problems. Consequently, I’m here to tell you that
aspartame
poisoning in dogs and cats is highly unlikely. (Which, to clarify, is not to say I
consider aspartame in any
way beneficial.)

Xylitol May Have Been to Blame

What more than likely happened to occasion this
dog’s death,
if indeed the story was true (beware: many Internet memes are
not), is that the
dog consumed a sugar-free yogurt containing xylitol, a sweetening
substance
increasingly found in all sorts of sugar-free consumer products.
Toothpaste,
mouthwash, gums, mints, candy, desserts, yogurts and even some of
those kids' vitamins and syrupy medications contain xylitol.

Because xylitol leads to a rapid drop in blood
sugar, many
dogs will collapse and suffer seizures. If they’re not rushed
immediately to
the hospital, they often die. In some cases, sudden death will
ensue even before
any other signs. And if they survive, they may suffer
life-threatening liver
failure.

Unfortunately, many pet owners (and even some
pet health
professionals!) are still unaware of this “natural” sweetener’s
extremely toxic
effects. In fact, depending on the amount ingested, it can be way
more toxic
to dogs than chocolate. And yet most dog owners are still in the
dark about the
poisons that lurk in their pockets and purses.

So if you
ever believe
your dog has been exposed to xylitol (or any potentially toxic
substance),
contact a pet poison control center and get to your veterinary clinic as soon as possible!

Note: Cat owners can rest easy. Not only are
cats not
adversely affected by xylitol (that we know of), but because they’re
not attracted
to sweet things (they don’t have taste buds that register “sweet”), they’re also less
likely to expose themselves to xylitol or any other sweetener.
(Enticingly creamy
delicacies are an exception.)